This invention relates to means for securing together containers and has particular, though not exclusive, application to such means for co-operating with the corner fittings of standard freight containers.
Freight containers are produced in a series of standard sizes and are known as I.S.O. containers. These containers are provided with corner fittings each of which comprises a hollow, generally box-shaped component provided with apertures in the outwardly facing walls thereof for receiving therein releasable securing means. Hereinafter any reference to a corner fitting is to be understood as referring to a corner fitting of the above-described type.
It is conventional practice to transport large numbers of such containers, usually a mix of 20 feet long and 40 feet long containers, on board ships with laterally adjacent containers interconnected with one another to form a stable block of containers.
It is also conventional practice to provide a matrix of upright steel columns or cell guides throughout the ship for locating the containers prior to interconnection, and clearly the precise location of these columns will depend upon the length of the containers to be transported. Thus, with a mixed load of 20 feet and 40 feet containers, it is necessary to provide cell guides some of which are spaced 20 feet apart and some of which are spaced 40 feet apart.
The fitting and removal of these upright steel columns is a tedious and time-consuming exercise which considerably increases the turnround time of the vessels in port.
It would be much more convenient to be able to provid a matrix of fixed-positioned cell guides but which still provided the necessary location for containers of different sizes and which therefore eliminated the necessity for fitting and removing guides in dependence upon the sizes of the containers to be transported.
This could be achieved by locating the cell guides at a spacing equal to the length of the longest containers to be transported, usually 40 feet, and by providing means for securing together end-to-end two 20 feet long freight containers into a 40 feet long unit capable of withstanding the loads associated with shipping.